Bladder and/or Rectum Extender with Exchangeable and/or Slideable Tungsten Shield

ABSTRACT

A method of using a shielding device with an applicator includes inserting the distal portion of the shielding device to a treatment site of a patient, the shield being made of plastic, imaging the treatment site, planning treatment of the treatment site based on the imaging, setting up the patient for treatment, imaging the treatment site, removing the distal portion of the shielding device from the treatment site, exchanging the shield made of plastic with a shield made of tungsten, inserting the distal portion of the shielding device to the treatment site, the shield being made of tungsten, imaging the treatment site, and performing the treatment.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation application of U.S. patentapplication Ser. No. 13/540,193, filed on Jul. 2, 2012, which claims thebenefit of U.S. Provisional Patent Application No. 61/504,064, filed onJul. 1, 2011, and claims the benefit of U.S. Provisional PatentApplication No. 61/512,387, filed on Jul. 27, 2011, each of which isexpressly incorporated herein in their entirety by reference thereto.

FIELD OF THE INVENTION

The present invention relates generally to a shielding device for useduring radiation treatment, an assembly comprising the shielding device,and a method of using the shielding device.

BACKGROUND INFORMATION

During treatment of cancer, for example, using either external beamradiation and/or high dose rate brachytherapy, other healthy organs maybe subjected to undesirable radiation due to their anatomical locationwith respect to a treatment site. For example, during treatment ofcancer of a cervix, a patient's rectum and/or bladder may be subjectedto undesirable radiation due to their proximity to the cervix.

Medical practitioners have long been plagued by the undesirable exposureto radiation of healthy organs while delivering a prescribed dose ofradiation to a treatment site, such as a patient's cervix. Therefore,there is believed to be a need to prevent such undesirable exposure toradiation of healthy organs while providing the prescribed dose ofradiation to the treatment site.

SUMMARY

Example embodiments of the present invention prevent undesirableexposure to radiation of healthy organs, for example, the rectum and/orbladder when treating a patient's cervix, by physically lifting and/orpushing the rectum and/or bladder away from the treatment site as far asanatomically possible using a shielding device. For example, the bladdermay be lifted up from its sagging position and pushed anterior and awayfrom the cervix.

In addition to the physical displacement of healthy organs, theshielding device may include an exchangeable and/or moveable shield, forexample, made of tungsten, to further reduce exposure to radiation ofhealthy organs. The shield may be removed, exchanged, and/or moved asrequired in order to facilitate imaging, treatment planning, and/oractual treatment.

In accordance with example embodiments of the present invention, ashielding device may include two elongated, parallel tubes joined at adistal portion, and a shield at least one of removably and slidablysituated at the distal portion. The distal portion may be angled up toabout 10 degrees relative to a plane defined by the tubes, and mayinclude at least one of a U-shaped and a circular portion. The tubes mayinclude markings configured to indicate a longitudinal position, and maybe made of medical grade titanium.

The shield may be made of tungsten/or and brass, and may be betweenabout 2 mm to about 5 mm thick. The shield may be configured to extendat least a length of the distal portion along a longitudinal axis of thetubes. In addition, the shield may include grooves for attachment to thetubes.

Further, the distal portion may include a separate shield retainerattached to distal ends of the tubes. The shield retainer may include aretaining lip and a key slot configured to retain the shield, and theshield may include a retaining ring and a key portion configured to bereceived by the retaining lip and the key slot, respectively.

The shielding device may be configured to be attached to an applicatorvia a rotary unit and an assembly block. The shielding device may bemovable within the rotary unit and the assembly block at least one oflongitudinally along a longitudinal axis of the tubes and rotationallytowards or away from a distal end of the applicator. The shieldingdevice may be configured to at least one of move and shield one of abladder and a rectum during treatment of a patient's cervix.

In accordance with example embodiments of the present invention, anassembly may include an applicator configured for a treatment site, anassembly block attached to the applicator, at least one rotary unitconfigured to be rotatably received in the assembly block, and at leastone shielding device, each respective shielding device including twoelongated, parallel tubes joined at a distal portion, and a shield atleast one of removably and slidably situated at the distal portion, inwhich the tubes of a respective shielding device are configured to bemovably received in a respective rotary unit.

The assembly, except for the shield, may be made of medical gradetitanium. The assembly block may be attached to the applicator via anapplicator lock screw, and may include a circular hole, an elongatedhole, and/or a U-shaped hole for receiving the applicator.

The rotary unit may be rotatably retained in the assembly block via acapture screw. The tubes may be secured in the rotary unit via shielddepth lock screws. The rotary unit may include a pivot pin, and theassembly block may include at least one angle adjustment screwconfigured to interact with the pivot pin, the pivot pin and the angleadjustment screw configured to set a rotational position of the rotaryunit when received in the assembly block. The pivot pin may betriangular and/or rectangular. The at least one angle adjustment screwmay include an angle location lock nut configured to reproducibly setthe rotational position.

The shielding device may be configured to move and/or shield a bladderand/or a rectum during treatment of a patient's cervix.

In accordance with example embodiments of the present invention, amethod of using a shielding device with an applicator may includeinserting the distal portion of the shielding device to a treatmentsite, and adjusting a position of the distal portion relative to adistal end of the applicator. The adjusting may include setting alongitudinal depth of insertion of the distal portion, and setting arotational position of the distal portion relative to the distal end ofthe applicator. The method may further include after the adjusting,removing the distal portion of the shielding device from the treatmentsite, and reproducibly reinserting the distal portion to a previouslyadjusted position. The method may further include moving, removing,and/or exchanging the shield. The method may further include sliding theshield relative to the tubes while the distal portion of the shieldingdevice is inserted to the treatment site.

In accordance with example embodiments of the present invention, amethod of using at least one shielding device with an applicator, theshielding device including two elongated, parallel tubes joined at adistal portion, and a shield at least one of removably and slidablysituated at the distal portion, may include inserting the distal portionof the shielding device to a treatment site of a patient, the shieldbeing made of plastic; imaging the treatment site; planning treatment ofthe treatment site based on the imaging; setting up the patient fortreatment; imaging the treatment site; removing the distal portion ofthe shielding device from the treatment site; exchanging the shield madeof plastic with a shield made of tungsten; inserting the distal portionof the shielding device to the treatment site, the shield being made oftungsten; imaging the treatment site; and performing the treatment.

The method may further include after the inserting of the distalportion, adjusting a position of the distal portion relative to a distalend of the applicator. The adjusting may include setting a longitudinaldepth of insertion of the distal portion and/or setting a rotationalposition of the distal portion relative to the distal end of theapplicator.

The method may further include after the adjusting, and before theremoving of the distal portion, returning the distal portion to anunadjusted position.

The method may further include after the returning to the unadjustedposition, and after the removing and the inserting of the distalportion, reproducibly adjusting the distal portion to a previouslyadjusted position.

The method may further include at least one of moving and removing theshield.

The method may further include sliding the shield relative to the tubeswhile the distal portion of the shielding device is inserted to thetreatment site.

The imaging may include at least one of fluoroscopy, computed tomographyscanning, and magnetic resonance imaging.

Example embodiments of the present invention are described in moredetail below with reference to the appended Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a first exemplary embodiment of anassembly including a shielding device according to the presentinvention.

FIGS. 2A to 2C show perspective, top and side views of a first exemplaryembodiment of a portion of a shielding device according to the presentinvention.

FIGS. 3A to 3F show top, side, bottom, proximal end, top perspective andbottom perspective views of a first exemplary embodiment of a shieldaccording to the present invention.

FIGS. 4A and 4B show perspective views of different positions of a firstexemplary embodiment of the shielding device according to the presentinvention.

FIG. 5 shows a close-up, perspective view of a first exemplaryembodiment of a rotary unit according to the present invention.

FIGS. 6A to 6C show proximal end, top and side views of a firstexemplary embodiment of a portion of a rotary unit according to thepresent invention.

FIGS. 7A to 7C show top, side and distal end views of a first exemplaryembodiment of a pivot pin of a rotary unit according to the presentinvention.

FIGS. 8A and 8B show side and end views of a first exemplary embodimentof a shield depth lock screw of a rotary unit according to the presentinvention.

FIGS. 9A to 9D show top, side, proximal end and top perspective views ofa first exemplary embodiment of the shielding device, rotary unit andassembly block according to the present invention.

FIGS. 10A to 10D show top, proximal end, side and distal end views of afirst exemplary embodiment of a portion of an assembly block accordingto the present invention.

FIG. 11 shows a close-up, perspective view of a first exemplaryembodiment of a rotary unit and assembly block according to the presentinvention.

FIG. 12 shows a perspective view of a second exemplary embodiment of apartially assembled assembly including a shielding device according tothe present invention.

FIG. 13 shows a perspective view of a second exemplary embodiment of afully assembled assembly including a shielding device according to thepresent invention.

FIGS. 14A to 14C show top, side and proximal end views of the secondexemplary embodiment of a fully assembled assembly including a shieldingdevice according to the present invention.

FIGS. 15A to 15E show perspective, proximal end, top, cross-sectionaland side views of a second exemplary embodiment of a shield retainer ofa shielding device according to the present invention.

FIGS. 16A to 16D show perspective, proximal end, bottom and side viewsof a second exemplary embodiment of a shield of a shielding deviceaccording to the present invention.

FIG. 17 schematically shows a method of using an exemplary embodiment ofa shielding device according to the present invention.

FIG. 18 shows a perspective view of a third exemplary embodiment of afully assembled assembly including a bladder shielding device and arectal retractor according to the present invention.

FIGS. 19A to 19D show perspective, top, side and proximal end views of athird exemplary embodiment of a rectal retractor according to thepresent invention.

FIGS. 20A to 20E show perspective, top, side, bottom and proximal endviews of a third exemplary embodiment of a shield of a rectal retractoraccording to the present invention.

DETAILED DESCRIPTION

FIG. 1 shows a perspective view of a first exemplary embodiment of anassembly 1 including a shielding device 20 according to the presentinvention.

The assembly 1 may be designed for use with high dose rate ring-tandemapplicators 10, high dose rate split ring applicators, or other suitableapplicators. Regardless of the specific type of applicator used with theassembly 1, the shielding device 20 provides displacement and/orshielding of healthy organs near the treatment site.

The assembly includes an applicator 10, a shielding device 20, a rotaryunit 30, and an assembly block 40. As shown in FIG. 1, the applicator 10may be a ring-tandem applicator including a ring 11 and a tandem 12joined to each other at a block 13. Optionally, the applicator 10 mayinclude a rectal retractor 14, also joined at the block 13. Although aparticular embodiment of an applicator 10 is shown in the Figures, it isunderstood that any suitable applicator may be used with the shieldingdevice 20.

FIGS. 2A to 2C show perspective, top and side views of a first exemplaryembodiment of a portion of a shielding device 20.

As shown in FIGS. 1 to 2C, the shielding device 20 includes two tubes 21that extend longitudinally substantially parallel with each other andwith the applicator 10. At a distal end of the tubes 21, the shieldingdevice 20 includes a substantially circular and/or U-shaped distalportion 22 that joins the two tubes 21. Alternatively, the distalportion 22 may include other shapes, e.g., oval, polygonal, and others.The tubes 21 and distal portion 22 may extend approximately 9½ inches,and the diameter of the tubes may be approximately ⅛ inch. The proximalends of the tubes 21 may include spherical buttons (not shown) forsafety and/or aesthetics. The tubes 21 and distal portion 22 may be madeof medical grade titanium, for example. Further, as shown in FIG. 2C,the distal portion 22 may be angled relative to a plane defined by thetwo tubes 21 by up to 10 degrees, preferably about 5 degrees.

FIGS. 3A to 3F show top, side, bottom, proximal end, top perspective andbottom perspective views of a first exemplary embodiment of a shield 23.FIGS. 4A and 4B show perspective views of different positions of a firstexemplary embodiment of the shielding device 20.

The shield 23 includes a proximal section 24 and a distal section 25.The proximal section 24 and at least a part of the distal section 25include grooves 26 that allow the shield 23 to be snapped into positionbetween the two tubes 21 and to be slid longitudinally between the twotubes 21, as shown in FIGS. 4A and 4B. The distal section 25 is shapedto correspond to the distal portion 22 of the shielding device 20, whichmay be substantially circular, for example, as shown in FIGS. 2A to 4B.The shield 23 may be configured to extend at least a length of thedistal section 25 along a longitudinal axis of the two tubes 21.Preferably, the shield 23 extends beyond the distal section 25 into theproximal section 24 such that the shield 23 may be reliably securedbetween the two tubes 21 by grooves 26. The shield 23 may be made oftungsten and/or brass, for example. Further, the shield 23 may bebetween about 2 mm thick to about 5 mm thick, preferably about 3 mmthick.

When the shield 23 is slid proximally, as shown in FIG. 4A, a positionof the shielding device 20 may be more easily confirmed by imaging,e.g., fluoroscopy, CT scanning, and/or MRI. The shield 23 may be sliddistally, as shown in FIG. 4B, prior to beginning treatment.Alternatively, the shield 23 may be removed, exchanged, and/orpositioned as necessary during all phases of imaging, treatmentplanning, and actual treatment.

FIG. 5 shows a close-up, perspective view of a first exemplaryembodiment of a rotary unit 30.

The rotary unit 30 includes shielding device receiving portions 31having receiving holes 32 and shield depth lock screws 33. The shieldingdevice receiving portions 31 are joined by a bearing portion 34 having apivot pin 35. The two tubes 21 of the shielding device 20 are receivedin the holes 32. The tubes 21 may be adjusted longitudinally to adesired insertion depth, and the tubes 21 may be locked in position byrotating the shield depth lock screws 33. The rotary unit 30 may be madeof medical grade titanium, for example.

FIGS. 6A to 6C show proximal end, top and side views of a firstexemplary embodiment of a portion of a rotary unit 30. FIGS. 7A to 7Cshow top, side and distal end views of a first exemplary embodiment of apivot pin 35 of a rotary unit 30. FIGS. 8A and 8B show side and endviews of a first exemplary embodiment of a shield depth lock screw 33 ofa rotary unit 30.

The rotary unit 30 includes shielding device receiving portions 31having receiving holes 32. The shielding device receiving portions 31are joined by a bearing portion 34. The bearing portion 34 includes apivot pin receiving hole 36, as shown in FIGS. 6A and 6B, in which apivot pin 35 may be inserted, preferably permanently. The pivot pin 35,as shown in 7A to 7C, includes an inserting pin 37 that is received bypivot pin receiving hole 36. Alternatively, the pivot pin 35 may beformed integrally with bearing portion 34 of rotary unit 30. The pivotpin 35 may be triangular in order to provide a range of angles of theshielding device 20 relative to the applicator 10. Alternatively, othershapes of the pivot pin 35 may be possible, such as for example,rectangular, circular, and/or polygonal, as long as a sufficient rangeof angles of the shielding device 20 relative to the applicator 10 ispossible. The shield depth lock screws 33, as shown in FIGS. 8A and 8B,may be held captive in the rotary unit 30, such that they cannot becompletely removed from the rotary unit 30. Further, the screws 33 mayhave knurled surfaces to facilitate manual operation of the screws 33.

FIGS. 9A to 9D show top, side, proximal end and top perspective views ofa first exemplary embodiment of the shielding device 20, rotary unit 30,and assembly block 40. FIGS. 10A to 10D show top, proximal end, side anddistal end views of a first exemplary embodiment of a portion of anassembly block 40.

The assembly block 40 is configured to receive the applicator 10 and therotary unit 30, to which the shielding device 20 is attached. As shownin FIGS. 10A to 10D, the assembly block 40 includes a circular hole 41and a U-shaped hole 42 configured to received the applicator 10.Further, the assembly block 40 includes an applicator lock screwreceiving hole 44 that receives an applicator lock screw, e.g., similarto shield depth lock screw 33, that locks the applicator 10 relative tothe assembly block 40. Alternative arrangements, such as for example,elongated holes and/or slots, may be possible to receive and lock theapplicator 10 in the assembly block 40. The assembly block 40 mayinclude additional holes 43 for weight reduction. In addition, theassembly block 40 includes a rotary unit receiving portion 46 and anangle adjustment screw hole 47 that receives an angle adjustment screwconfigured to interact with the rotary unit 30 to set an angle of theshielding device 20 relative to the applicator 10. The assembly block 40may be made of medical grade titanium, for example.

FIG. 11 shows a close-up, perspective view of a first exemplaryembodiment of a rotary unit 30 and assembly block 40.

The applicator 10, including ring 11, tandem 12 and optional rectalretractor 14 held together by block 13, is received in holes 41, 42 ofassembly block 40 and locked in place by applicator lock screw 45. Inaddition, tubes 21 of shielding device 20 are received in rotary unit 30and locked in place by shield depth lock screws 33. Further, the bearingportion 34 of rotary unit 30 is received in rotary unit receivingportion 46 of assembly block 40. Angle adjustment screw 48 is adjustedto interact with pivot pin 35 of rotary unit 30 to set an angle ofshielding device 20 relative to applicator 10. The shielding device 20is movable within the rotary unit 30 longitudinally along a longitudinalaxis of the two tubes 21. Additionally, the shielding device 20 androtary unit 30 are movable within the assembly block 40 rotationallytowards or away from a distal end of the applicator 10.

The assembly 1 including the shielding device 20 is configured to moveand/or shield a bladder and/or a rectum during treatment of a patient'scervix. Thus, the shielding device 20 allows for following the principleof radiation protection: time, distance, and shielding. That is, theduration of radiation treatment can be optimally set for the treatmentsite without compromising the prescription dose, while protectinghealthy organs via increased distance and/or shielding from radiationexposure.

FIG. 12 shows a perspective view of a second exemplary embodiment of apartially assembled assembly 100 including a shielding device 120. FIG.13 shows a perspective view of a second exemplary embodiment of a fullyassembled assembly 100 including a shielding device 120. FIGS. 14A to14C show top, side and proximal end views of the second exemplaryembodiment of a fully assembled assembly 100 including a shieldingdevice 120.

As shown in the Figures, the assembly 100 includes an applicator 110,two shielding devices 120, two rotary units 130 and an assembly block140. The applicator 110 includes a ring 111 and tandem 112 joined at ablock 113. The assembly 100 may be designed for use with high dose ratering-tandem applicators 110, high dose rate split ring applicators, orother suitable applicators. Regardless of the specific type ofapplicator used with the assembly 100, the shielding device 120 providesdisplacement and/or shielding of healthy organs near the treatment site.

FIGS. 15A to 15E show perspective, proximal end, top, cross-sectionaland side views of a second exemplary embodiment of a shield retainer 122of a shielding device 120. FIGS. 16A to 16D show perspective, proximalend, bottom and side views of a second exemplary embodiment of a shield123 of a shielding device 120.

Each shielding device 120 includes two tubes 121, a shield retainer 122at a distal end of the tubes 121, and a shield 123. The shield retainer122 is substantially circular and/or U-shaped and joins distal ends ofthe two tubes 121. Alternatively, the shield retainer 122 may includeother shapes, e.g., oval, polygonal, and others. The tubes 121 andshield retainer 122 may extend approximately 9½ inches, and the diameterof the tubes may be approximately ⅛ inch. The proximal ends of the tubes121 may include spherical buttons (not shown) for safety and/oraesthetics. The tubes 121 and shield retainer 122 may be made of medicalgrade titanium, for example. Further, the shield retainer 122 may beangled relative to a plane defined by the two tubes 121 by up to 10degrees, preferably about 5 degrees.

The shield 123 may be shaped to correspond to the shield retainer 122 ofthe shielding device 120. The shield 123 may be made of tungsten and/orbrass, for example. Further, the shield 123 may be between about 2 mmthick to about 5 mm thick, preferably about 3 mm thick.

In addition, as shown in FIGS. 15A to 15E, the shield retainer 122 mayinclude a retaining lip 124 and a key slot 125 configured to retain theshield 123. As shown in FIGS. 16A to 16D, the shield 123 may include aretaining ring 126 and a key portion 127 configured to be received bythe retaining lip 124 and the key slot 125, respectively, of the shieldretainer 122.

When the shield 123 is to be attached to the shield retainer 122, theshield 123 may be rotated and attached to shield retainer 122 such thatthe retaining ring 126 is inserted within the periphery of the shieldretainer 122 and the retaining lip 124 does not abut against retainingring 126 of shield 123. Then, the shield 123 may be rotated to engageretaining lip 124 with retaining ring 126. Further, when the shield 123is fully rotated to the assembled position as shown in FIG. 13, forexample, the key portion 127 of shield 123 may be received within keyslot 125 of shield retainer 122. Thus, the shield 123 may be positivelysecured within shield retainer 123 to prevent inadvertent disassembly ofthe shield 123 from the shielding device 120, especially duringtreatment. The shield 123 may be removed by reversing the order of thesteps described above. The shield 123 may be removed, exchanged, and/orpositioned as necessary during all phases of imaging, treatmentplanning, and actual treatment.

As shown in FIGS. 12 to 14C, each rotary unit 130 includes shieldingdevice receiving portions 131 having receiving holes 132 and shielddepth lock screws 133. The shielding device receiving portions 131 arejoined by a bearing portion 134 having a pivot pin 135. The tubes 121 ofeach shielding device 120 are received and longitudinally situatedwithin receiving holes 132 of a respective rotary unit 130. The tubes121 may be adjusted longitudinally to a desired insertion depth, and thetubes 121 may be locked in position by rotating the shield depth lockscrews 133. The tubes 121 may further include markings and/or grooves128 that indicate a depth of insertion of the shielding device 120. Forexample, the markings 128 may be placed every 5 mm and/or 1 cm, or anyother length, along the tubes 121. In addition, the markings 128 may bethe same or different from each other. By the use of such markings 128,a longitudinal position of the shielding device 120 may be set such thatthe shielding device 120 may be reproducibly inserted to a desireddepth. The rotary unit 130 may be made of medical grade titanium, forexample.

The pivot pin 135 may be triangular in order to provide a range ofangles of the shielding device 120 relative to the applicator 110.Alternatively, other shapes of the pivot pin 135 may be possible, suchas for example, rectangular, circular, and/or polygonal, as long as asufficient range of angles of the shielding device 120 relative to theapplicator 110 is possible. The shield depth lock screws 133 may be heldcaptive in the rotary unit 130, such that they cannot be completelyremoved from the rotary unit 130. Further, the screws 133 may haveknurled surfaces to facilitate manual operation of the screws 133.

The assembly block 140 receives ring 111 and tandem 112 of applicator110 in holes 141, 142 of assembly block 140, and the applicator lockscrew 145 secures the applicator 110 in place. The assembly block 140may be made of medical grade titanium, for example.

In addition, the bearing portion 134 of each rotary unit 130 is receivedin a rotary unit receiving portion 146 of assembly block 140. Afterinsertion, the bearing portion 134 may be retained, while maintainingrotational freedom, by a capture screw 150. The angle of the rotary unit130 may be adjusted by inserting, into angle adjustment screw hole 147,an angle adjustment screw 148 that interacts with the pivot pin 135 ofthe rotary unit 130. Further, an angle location lock nut 149 may beprovided on angle adjustment screw 148 to reproducibly set a rotationalposition of rotary unit 130. That is, when the angle adjustment screw148 is inserted to a desired depth, the angle location lock nut 149 maybe turned to abut against assembly block 140, thereby setting aninsertion depth of screw 148. Thereafter, screw 148 can be removed andreproducibly reinserted to the desired depth, thereby setting thedesired rotational position of rotary unit 130 and the attachedshielding device 120. Accordingly, the shielding device 120 is movablewithin the rotary unit 130 and can be set to a reproducible longitudinalposition along a longitudinal axis of the two tubes 121. Additionally,the shielding device 120 and rotary unit 130 are movable within theassembly block 140 and can be set to a reproducible rotational positionwith respect to a distal end of the applicator 110.

The assembly 100 including the shielding device 120 is configured tomove and/or shield a bladder and/or a rectum during treatment of apatient's cervix. Further, as shown in FIGS. 12 to 14C, by the provisionof a shielding device 120 on opposite sides of the applicator 110, oneshielding device may shield the bladder and the other shielding devicemay simultaneously shield the rectum during radiation treatment of apatient's cervix. Thus, the shielding device 120 allows for followingthe principle of radiation protection: time, distance, and shielding.That is, the duration of radiation treatment can be optimally set forthe treatment site without compromising the prescription dose, whileprotecting healthy organs via increased distance and shielding fromradiation exposure.

FIG. 17 schematically shows a method 200 of using an exemplaryembodiment of a shielding device.

At step 202, a distal end of an applicator may be inserted to atreatment site. At step 204, a distal portion of the shielding device isinserted to the treatment site, and at step 206, a position of thedistal portion is adjusted relative to a distal end of the applicator.The adjustment may include longitudinal and/or rotational adjustment ofthe shielding device relative to the applicator. That is, a longitudinaldepth of insertion of the shielding device may be adjusted and/orreproducibly set, for example, by moving the tubes 21, 121 based onmarkings 128 and thereafter locking the tubes by shield depth lockscrews 33, 133; a rotational position of the shielding device may beadjusted and/or reproducibly set, for example, by rotating the shieldingdevice and rotary unit using pivot pin 35, 135, angle adjustment screw48, 148 and angle location lock nut 149. After the adjustment at step206, the distal portion of the shielding device may be removed from thetreatment site at step 208. The shield may be moved, removed, and/orexchanged at step 210. Then, at step 212, the distal portion of theshielding device may be reproducibly reinserted to the previouslyadjusted position, i.e., the previously adjusted and/or set longitudinaland rotational positions. Alternatively or additionally, at step 214,the shield may be slid relative to the two tubes while the distalportion of the shielding device remains inserted to the treatment site.Finally, at step 216, radiation treatment may be performed.

At any point in the above-described method 200, imaging, e.g.,fluoroscopy, CT (computed tomography) scanning and/or MRI (magneticresonance imaging), may be performed to determine the position of theshielding device and/or the assembly relative to the treatment site. Forexample, to facilitate imaging of the position of the shielding device,the shielding device may initially have no shield or a shield ofdifferent material, e.g., plastic such as delrin, that does notinterfere with imaging. After adjustment of the position of theshielding device, the shield may be added or, in the case of a plasticshield, exchanged, prior to beginning radiation treatment. Optionally,the shielding device may be used without a shield during radiationtreatment, such that the shielding device then serves primarily to movethe bladder and/or rectum during treatment.

In a further exemplary embodiment of a method 200 of using a shieldingdevice, the method may comprise the following combination of steps:inserting the distal portion 204 of the shielding device to a treatmentsite of a patient, the shield being made of plastic; imaging thetreatment site; planning treatment of the treatment site based on theimaging; setting up the patient for treatment; imaging the treatmentsite; removing the distal portion 208 of the shielding device from thetreatment site; exchanging the shield 210 made of plastic with a shieldmade of tungsten; inserting the distal portion 212 of the shieldingdevice to the treatment site, the shield being made of tungsten; imagingthe treatment site; and performing the treatment 216.

When the distal portion of the shielding device is inserted 204, 212 tothe treatment site, a position of the distal portion may be adjusted206. The position of the distal portion may be adjusted before, duringand/or after imaging of the treatment site. The adjusting of theposition of the distal portion 206 may include setting a longitudinaldepth of insertion of the distal portion and/or setting a rotationalposition of the distal portion relative to the distal end of theapplicator, as more fully described above.

After the position of the distal portion has been adjusted 206 to thetreatment site, the distal portion may be returned to its unadjustedposition before removing the distal portion 208 from the treatment site.For example, the distal portion may be returned to its unadjustedposition by changing the rotational position and/or the longitudinalposition of the distal portion. It may be possible and/or preferable toreturn only the rotational position of the distal portion to theunadjusted position before removing the distal portion, and leaving thelongitudinal position of the distal portion in its adjusted state.

After the distal portion is returned to its unadjusted position, thedistal portion may be removed 208 from the treatment site. Afterremoving the distal portion 208, and exchanging the shield 210 made ofplastic with a shield made of tungsten, the distal portion may beinserted 212 into the treatment site again. Once inserted, a position ofthe distal portion may be reproducibly adjusted to a previously adjustedposition. Thus, the adjusting may only need to be completed one time fora particular treatment of a patient. Thereafter, the distal portion ofthe shielding device can be removed and inserted multiple times whilestill allowing the position of the distal portion to be reproduciblyadjusted to the previously adjusted position.

Further, the method may further include the step of moving and/orremoving 210, 214 the shield. For example, the moving may includesliding the shield 214 relative to the tubes while the distal portion ofthe shielding device is inserted to the treatment site. Additionally oralternatively, the shield may be moved and/or removed 210, 214 when thedistal portion is removed from the patient. Further, the distal portionmay be inserted to the treatment site without any shield, such that theshielding device then serves primarily to move the bladder and/or rectumduring treatment.

FIG. 18 shows a perspective view of a third exemplary embodiment of afully assembled assembly 300 including a bladder shielding device 320and a rectal retractor 360.

As shown in FIG. 18, the assembly 300 includes an applicator 310, abladder shielding device 320, a rectal retractor 360, two rotary units330, one for each of the bladder shielding device 320 and the rectalretractor 360, and an assembly block 340. The applicator 310 includes aring and tandem joined at a block, similar to that described withreference to the first and second exemplary embodiments. The assembly300 may be designed for use with high dose rate ring-tandem applicators310, high dose rate split ring applicators, or other suitableapplicators. Regardless of the specific type of applicator used with theassembly 300, the bladder shielding device 320 and the rectal retractor360 provide displacement and/or shielding of healthy organs, i.e.,bladder and rectum, respectively, near the treatment site.

The bladder shielding device 320 is similar to that described withreference to the first exemplary embodiment. For example, as shown inFIG. 18, the bladder shielding device 320 includes a substantiallycircular distal portion that joins the two tubes and a correspondinglyshaped shield, and the distal portion is angled relative to a planedefined by the two tubes by about 5 degrees. The rotary units 330 aresimilar to those described with reference to the first and secondexemplary embodiments, and the assembly block 340 is similar to thatdescribed with reference to the second exemplary embodiment.

FIGS. 19A to 19D show perspective, top, side and proximal end views of athird exemplary embodiment of a rectal retractor 360. FIGS. 20A to 20Eshow perspective, top, side, bottom and proximal end views of a thirdexemplary embodiment of a shield 363 of a rectal retractor 360.

The rectal retractor 360 includes two tubes 361 that extendlongitudinally substantially parallel with each other and with theapplicator 310. At a distal end of the tubes 361, the rectal retractor360 includes a substantially U-shaped distal portion 362 that joins thetwo tubes 361. Accordingly, the rectal retractor 360 may resemble a“tuning fork,” in which the distal portion 362 does not have an enlargedcircular shape and is not angulated. In addition, the distal portion 362does not substantially extend laterally beyond the substantiallyparallel, longitudinally extending tubes 361. The tubes 361 and distalportion 362 may extend approximately 9½ inches, and the diameter of thetubes may be approximately ⅛ inch. The proximal ends of the tubes 361may include spherical buttons (not shown) for safety and/or aesthetics.The tubes 361 and distal portion 362 may be made of medical gradetitanium, for example.

The shield 363 includes a proximal section 364 and a distal section 365.The proximal section 364 and at least a part of the distal section 365include grooves 366 that allow the shield 363 to be snapped intoposition between the two tubes 361 and to be slid longitudinally betweenthe two tubes 361. The distal section 365 is shaped to correspond to thedistal portion 362 of the rectal retractor 360, which may besubstantially U-shaped and resemble a “tuning fork,” for example. Theshield 363 may be configured to extend at least a length of the distalsection 365 along a longitudinal axis of the two tubes 361. Preferably,the shield 363 extends beyond the distal section 365 into the proximalsection 364 such that the shield 363 may be reliably secured between thetwo tubes 361 by grooves 366. The shield 363 may be made of tungstenand/or brass, for example. Further, the shield 363 may be between about2 mm thick to about 5 mm thick, preferably about 3 mm thick.

When the shield 363 is slid proximally, a position of the tubes 361 ofthe rectal retractor 360 may be more easily confirmed by imaging, e.g.,fluoroscopy, CT scanning, and/or MRI. The shield 363 may be sliddistally, prior to beginning treatment. Alternatively, the shield 363may be removed, exchanged, and/or positioned as necessary during allphases of imaging, treatment planning, and actual treatment. Forexample, to facilitate imaging, a plastic shield 363 may be insertedinto the rectal retractor 360 in place of a tungsten shield 363, similarto that described with reference to the shielding device in the methodof FIG. 17.

A rotary unit 330 and assembly block 340 may receive the rectalretractor 360 in a manner similar to that described with reference tothe shielding device, rotary unit and assembly block of the first andsecond exemplary embodiments. For example, the rectal retractor 360 maybe longitudinally and/or rotationally adjusted, and/or locked inposition, within rotary unit 330 and assembly block 340. In addition,the two tubes 361 of the rectal retractor 360 may include markingsand/or grooves that indicate a depth of insertion of the rectalretractor 360, such that a longitudinal position of the rectal retractor360 may be set, and the rectal retractor 360 may be reproduciblyinserted to a desired depth. Thus, the rectal retractor 360 is movablewithin the rotary unit 330 and can be set to a reproducible longitudinalposition along a longitudinal axis of the two tubes 361. Additionally,the rectal retractor 360 and rotary unit 330 are movable within theassembly block 340 and can be set to a reproducible rotational positionwith respect to a distal end of the applicator 310.

The assembly 300 including the bladder shielding device 320 and rectalretractor 360 is configured to move and/or shield a bladder and arectum, respectively, during treatment of a patient's cervix. As shownin FIGS. 18 to 20E, by the provision of a bladder shielding device 320and a rectal retractor 360 on opposite sides of the applicator 310, theshielding device 320 may move and/or shield the bladder and the rectalretractor 360 may simultaneously move and/or shield the rectum duringradiation treatment of a patient's cervix. Thus, the shielding device320 and rectal retractor 360 allow for following the principle ofradiation protection: time, distance, and shielding. That is, theduration of radiation treatment can be optimally set for the treatmentsite without compromising the prescription dose, while protectinghealthy organs via increased distance and shielding from radiationexposure.

In all of the above exemplary embodiments having a shielding device forthe bladder and a shielding device or rectal retractor for the rectum,each of the shielding devices and/or rectal retractor may be manipulatedindividually and/or independently of each other. Alternatively oradditionally, each shielding device and/or rectal retractor for eitherthe bladder or the rectum may be used only one-at-a-time. That is, onlya shielding device for the bladder may be used, or only a shieldingdevice or rectal retractor for the rectum may be used.

Further, all of the above exemplary embodiments and any combinationsthereof may be used according to the various method described withreference to FIG. 17. For example, with respect to the various methodsdescribed with reference to FIG. 17, all references to a shieldingdevice and shield may alternatively and/or additionally refer to therectal retractor 360 and shield 363 according to the third exemplaryembodiment.

For performing the radiation treatment, Ir-192 may preferably be used.Alternatively, other suitable radiation sources may also be used.

Although the present invention has been described with reference toparticular examples and exemplary embodiments, it should be understoodthat the foregoing description is in no manner limiting. Moreover, thefeatures described herein may be used in any combination.

1. A method of using at least one shielding device with an applicator,the shielding device including two elongated, parallel tubes joined at adistal portion, and a shield at least one of removably and slidablysituated at the distal portion, comprising: inserting the distal portionof the shielding device to a treatment site of a patient, the shieldbeing made of plastic; imaging the treatment site; planning treatment ofthe treatment site based on the imaging; setting up the patient fortreatment; imaging the treatment site; removing the distal portion ofthe shielding device from the treatment site; exchanging the shield madeof plastic with a shield made of tungsten; inserting the distal portionof the shielding device to the treatment site, the shield being made oftungsten; imaging the treatment site; and performing the treatment. 2.The method according to claim 1, further comprising: after the insertingof the distal portion, adjusting a position of the distal portionrelative to a distal end of the applicator.
 3. The method according toclaim 2, wherein the adjusting includes setting a longitudinal depth ofinsertion of the distal portion.
 4. The method according to claim 2,wherein the adjusting includes setting a rotational position of thedistal portion relative to the distal end of the applicator.
 5. Themethod according to claim 2, further comprising: after the adjusting,and before the removing of the distal portion, returning the distalportion to an unadjusted position.
 6. The method according to claim 5,further comprising: after the returning to the unadjusted position, andafter the removing and the inserting of the distal portion, reproduciblyadjusting the distal portion to a previously adjusted position.
 7. Themethod according to claim 1, further comprising: at least one of movingand removing the shield.
 8. The method according to claim 1, furthercomprising: sliding the shield relative to the tubes while the distalportion of the shielding device is inserted to the treatment site. 9.The method according to claim 1, wherein the imaging includes at leastone of fluoroscopy, computed tomography scanning, and magnetic resonanceimaging.